A single closed loop direct exchange geothermal power production system that utilizes a refrigerant working fluid in at least one of three primary designs to generate electrical power from deep wells: with a first version of a direct exchange geothermal power generating system operating primarily on refrigerant vapor pressure; with a second version of a direct exchange geothermal power generating system operating primarily on liquid refrigerant gravitational pressure; and with a third version of a direct exchange geothermal power generating system operating primarily on both liquid refrigerant gravitational pressure and refrigerant phase change/expansion from a liquid to a vapor state.